The United States population is growing older and persons are living longer. Yet older persons have been leaving the labor force at younger and younger ages. Moreover, most Americans have said very little. At the same time, the cost of medical care has been increasing. It is likely that the trend toward earlier retirement will be reversed and demographic forces will squeeze the young to save more. The cost of medical care may continue to increase. The same forces are at work in virtually all industrialized countries. Thus understanding the determinants of retirement, understanding the nature of saving for retirement, and understanding the nature of saving for retirement, and understanding how to more efficiently determine medical care are perhaps the most critical issues that demographic trends have forced upon us. With past trends and likely future trends providing the focus, the program project will aim to: (1) Assess the implications of expanding personnel retirement saving for the level, distribution, and risk of future retirement wealth. (2) Improve the potential of accurate measurement of wealth and other household attributes in surveys like the HRS and AHEAD, by developing experimental methods that can be used to determine the implications of alternative survey designs. (3) Determine the effect of social security provisions on retirement in twelve industrialized countries, to understand the political and economic determinants of current provisions, and to assess the implications of early retirement for political and economic determinants of current provisions, and to assess the implications of early retirement for foregone productive capacity. (4) Understand he relationship between wealth and health over the life cycle, making comparisons across and within nations, and between and within populations subgroup. (5) Understand the relationship between the medical expenditures and employees and the provisions of firm health insurance plans. (6) Understand the distribution the medical expenditures in the U.S. elderly population, how they are financed, and the health and other factors that determine expenditures and expenditure growth. (7) Assess the nature of access to health care, measured by both insurance coverage and the treatment that is available to insurance plan members. The Program Project is the foundation of a substantially larger NBER program on the economics of aging and health care and has the goals that are substantially broader than the specific research aims listed above. In general, the program aims to promote research among a broader group of economists at the NBER, nationwide, and abroad, and to foster training of young economists who will subsequently contribute to the overall research effort. In addition, the program aims to expand and maintain the data bank that supports a large amount of fundamental research.